As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Information handling systems and other devices often utilize blower apparatus or cooling fans to regulate temperature generated within a chassis of the device. For example, notebook computers and similar devices often employ a blower to cool the system chipset together with other heat sources that may be present within the chassis. Due to notebook computer architecture and component placement, the blower inlet is typically defined in the bottom of the system where there is a greater probability that the blower fan will ingest dirt, lint and other impurities that over time tend to clog the thermal heat sink and/or other system components, leading to reduced thermal efficiency of the system. When this occurs, higher system temperatures result which leads to frequent activation of over temperature protection (OTP).
FIG. 1 illustrates a conventional axial fan assembly 100, such as may be employed for cooling of a high voltage projector bulb 150 in a slide projector, or for cooling a server chassis. In such applications, sufficient room must be available within the chassis to accommodate the axial fan assembly 100. As shown in FIG. 1, axial fan assembly includes a fan housing 102 that surrounds an axial fan and heat sink 104. In FIG. 1, the axial fan is rotating in a first direction to draw in air though fan inlet 106 and expel the air from fan outlet 108. As shown fan inlet 106 and fan outlet 108 are positioned in line with the rotational axis of the fan and the axial fan moves air through fan assembly 100 in an axial direction, i.e., in a direction parallel and in-line to with the rotational axis of the fan as illustrated by the arrows in FIG. 1. When so rotated, the axial fan draws air into the projector or server system chassis for purposes of dissipating heat from heat generating components therein.
FIG. 2 illustrates the conventional axial fan assembly 100 of FIG. 1 when the axial fan is rotating in a second direction that is opposite to the first direction of FIG. 1. As shown in FIG. 2, air is moved in a direction opposite to that of FIG. 1 when the rotation of the axial fan is reversed such that air is now drawn in though fan outlet 108 and expelled from fan inlet 106, once again in a direction parallel and in-line to with the rotational axis of the fan as illustrated by the arrows in FIG. 2. By so reversing the axial fan direction, air may be expelled from a projector or server system chassis in a manner that removes accumulated dust from the chassis.
Centrifugal fan apparatus in the form of blowers are also employed to cool information handling systems such as notebook computers. Such blowers use a vaned rotor or bladed impeller that rotates within a blower stator housing. Unlike axial fan assemblies, such blowers draw in air at an axial opening near the shaft of the impeller and blow air out an opening that is located circumferentially to the impeller and in a direction that is oriented at a right angle to the direction of air intake. Further, such blowers always intake air from the axial air opening and exhaust the air from the circumferential opening, regardless of the direction of rotation of the impeller. FIG. 3 illustrates an example of a conventional blower assembly 150 having a stator housing 156 with a vaned rotor 154 coupled thereto to rotate about its center axis relative to the stator housing 156. A stator housing cover 160 is configured with an axial air opening 162 defined therein to overlie rotor component 154 when assembled thereto as shown by the dotted lines. An air exhaust opening 159 is shown present for exhausting air from blower 150. Rotor 154 includes angled directional vanes and rotor component is rotatably received within a rotor cavity 158 defined in stator housing 156. Directions of rotor rotation, air intake, and air exhaust for conventional blower 150 are indicated by the arrows in FIG. 3. Such a blower 150 may be installed within the chassis of an information handling system, such as notebook computer, in a manner such that axial air opening 162 extends through an outside wall of the chassis to draw in external cooling air, and such that air exhaust opening 159 exhausts cooing air into the interior of the chassis during blower operation.